NORMANDY CONQUEST
Last issue we detailed remarkable performances between Paris and Rouen – but how do the French locomotives fare when the topography isn’t so accommodating?
In SR477 I gave details of SNCF ‘Pacific’ performance on the mainly level Paris to Rouen route as a comparison with Tornado’s run between Durham and York. My correspondent John Forman has suggested it would be of interest to see how the ‘Pacifics’ performed on the hillier section between Rouen and Le Havre and I am happy to oblige. The line climbs to the Normandy plateau and finally descends steeply to the coast. As can be seen from the gradient profile on pages 94-95 of SR477, there is a steady ascent all the way to Motteville, apart from a brief remission of the gradient down to Barentin Viaduct. As I mentioned in SR477, the engineer of the Paris-Le Havre line was Englishman Joseph Locke (1805-60) who appointed Thomas Brassey and William Mackenzie as joint contractors. Brassey suffered a major embarrassment in January 1846 when the Barentin Viaduct over the River Austreberthe, the principal structure on the line, collapsed after a period of prolonged rain, fortunately without any loss of life. This disaster was ascribed to substandard local materials being used in its construction. Brassey rebuilt the viaduct at his own expense with his own choice of materials. That viaduct still stands today, an imposing curved structure of 27 arches, 600 yards long and 100 feet high. Beyond Yvetôt the line is mainly downhill, culminating in a descent of almost 7 miles at 1-in-125 from ÉtainhusSt Romain to the outskirts of Le Havre, a steep challenge for heavy Paris-bound trains. Table 3 features two runs with 231D ‘Pacifics’. These were the basic État Pacific rebuilds of 1933-47 which ultimately numbered 134 examples. They had Lentz-Dabeg oscillating cam-poppet valves only on the inside (low pressure cylinders) but retained piston valves on the high pressure cylinders. Working pressure was 16 bars (228lb/sq in). In column 1, 231.D.702 was working the morning First Class-only ‘Rapide’ from
the journey was only 6 mins longer than that of the petrol-driven Bugatti railcars of the mid-1930s
Paris, Train 101, with a 130kph (80.8mph) speed limit and a load comfortably inside the 400 tonnes maximum for the timing. I had travelled through from Paris on the footplate and noted that the Flaman speed recorder was, unusually, reading slow by around 4kph. The Le Havre crew of Mécanicien Wust and Chauffeur Charlot were joined by Chef de Conduite Quiennec. Leaving Rouen on time, a brisk start was made up the gentle initial gradients, achieving 63mph at Malaunay and falling to 58mph up the succeeding stretch at 1-in-200. The dip over Barentin Viaduct caused speed to rise to 67mph before brakes were applied in anticipation of a 30mph tsr beyond Pavilly, which marred the climb to Motteville. Speed recovered to 55½mph before the summit of the 1-in-181. This was achieved using cut-offs of 35% HP/65% LP and a steam chest pressure of 214lb/sq in. The edbhp involved was around 1,400, according to my colleague David Pawson. After a maximum of 83mph at Yvetôt (remember this particular locomotive’s Flaman recorder was reading slow) the high speed continued and the arrival at Le Havre was 4 mins early, in a net time of 51½ mins from Rouen. Added to 231.D.702’s net running time of 73½ mins for the 86.70 miles from Paris, the overall net time for the
journey of 141.65 miles from Paris was 125 minutes, an average of 68mph. With a theoretical 1-min stop at Rouen, the journey was only 6 mins longer than that of the petrol-driven Bugatti railcars of the mid-1930s. They were permitted to travel at 140kph (87mph) but had a passenger capacity of only 48.
FATAL DISASTER
Sadly 231.D.702 and a different crew were involved in a fatal accident at Achères on November 4 1964 – only a few months after my own run. One wagon of a diesel-hauled freight train on the Grande-Ceinture line that diverges at Achères became derailed, fouling the Down main line just as 231.D.538 was approaching with Train 103, the 08.45 Paris-Le Havre express, which itself derailed with its tender obstructing the Up line on which 231.D.702 was travelling at speed on Train 102, the 06.55 Le Havre-Paris Rapide. In the ensuing crash, 231.D.702 uprooted a series of newly installed catenary masts and ended up on its side. There were four fatalities. In the circumstances of impending electrification, both 231Ds were deemed beyond economic repair and scrapped. Column 2 features a footplate run only nine days before steam ended, on the last of the batch of 40 North British-built locomotives, 231.D.689, on a Saturdays-only service, the 13.18 from St Lazare, loading to 13 vehicles of 515 tons gross. The Le Havre crew were Mécanicien Le Meur and Chauffeur Plouguerné with Chef de Conduite Sergent presiding. With its heavier train 231.D.689’s driver used 50% cut-off in the HP cylinders and 70% in the LP on the climb through the tunnels to Maromme and, by Malaunay, where speed was 56mph, he had reduced this to 45%/70%. Maximum edbhp on this climb was in the order of 1,700. The top of the bank at Motteville was crested at 48½mph using cut-offs of 45%HP/70%BP with boiler pressure at 217lb, but only 175lb in the steam chest: very easy running. After the Yvetôt stop, the ‘Pacific’ got away smartly down the favourable gradient to Allouville, and by Bolbec had covered the 12.10 miles from Yvetôt in under 13 mins, achieving 74½mph soon after. Two relaying slacks were in force, which ruined any prospect of picking up further time having left Rouen 6 mins late, but rapid acceleration down the bank from St Laurent produced an unusual maximum of 78½mph at Harfleur, swiftly checked using the brake.
FINAL FLING
Table 4 contains my last footplate run on the Le Havre line before steam finished, with 231.D.765 on a lightweight ‘Rapide’ and two runs with heavy trains just inside the 600-tonne limit, one with a 231G and the other with a 231D. The 231.D.765 run in column 1 was on the same day as my Down run with 231.D.689 in Table 3
and, therefore, the same Chef de Traction, M. Sergent, officiated. The Le Havre crew on 231.D.765, Mécanicien Henry and Chauffeur Boisset, made a spirited run that was somewhat spoiled by two severe temporary speed restrictions, one near the top of the 1-in-125 to Étainhus and the other near Bréauté. Column 2 features Mécanicien Henry two years earlier, this time on 231.G.588, the most powerful variant of État Pacific, with Lentz-Dabeg cam-poppet valves on all four cylinders and double Kylchap exhaust. The chauffeur was M. Barbey with Chef de Traction Quiennec officiating. The schedule was improved upon, despite a speed as low as 25½mph on Étainhus bank. After a reasonable start, in which around 1,200edbhp was achieved at Harfleur, by St Laurent cut-offs of 55% HP and 65% LP were employed from this point to the summit, with full regulator producing a negligible reduction in the HP steam chest from the steady 214lb boiler pressure on the climb, and giving 35lb in the LP steam chest. This level of performance on Étainhus bank was typical on heavy trains and sufficient to keep time, but in column 3 there is a remarkable performance four years earlier by 231.D.565 on a boat train out of the docks, connecting with the Southampton-Le Havre overnight ferry, where a superb recovery was made from a signal stop after Graville. Starting from rest, the 231D had almost equalled 231.G.588’s speed at St Laurent and continued to accelerate all the way up the bank to pass the summit in brilliant style at 36mph. I can only think that reinforced compound (that is admitting live steam direct to the LP cylinders) was employed to produce such an extraordinary performance. This practice was seldom employed with these engines except, universally, upon starting. David Pawson calculates the edbhp on this climb as only 1,350, though there is some doubt as to the validity of French locomotive and coach resistance values, which could affect all the power outputs quoted. On an average unchecked run on one of the ‘Rapides’, speed up Étainhus bank would be maintained in the mid-40s. It only remains to comment that the riding of these locomotives was superb, and to lament the fact that no 231D survives, the only État Pacific still extant being 231.G.558, which is maintained by the Pacific Vapeur Club at Sotteville, outside Rouen.